Turbulent radiant combustion chamber



Aug. 14, 1934. s. F. wALToN TURBULENT RADIANT COMBUSTION CHAMBER FiledApril 8, 1932 2 Sheets-Sheet l wezvzar E Worin@ Aug. 14, 1934. s F.wALToN TURBULENT RADIANT COMBUSTION CHAMBER Filed Apr-il 8, 1952 2Sheets-Sheety 2 l #AF Dzvenor fz fazlzzzeIPI/an Patented Aug. 14, 1934TURBULENT RADIANT COMSTO CHAMBER Samuel F. Walton, Hamburg, N. Y.,assgnor to The Exolon Company, Blasdell, N; Y., a corporation ofMassachusetts Application April 8, 1932, Serial No. 604,036 3 claims'.(ol. 15s-1) This invention relates to combustion 'chambers andparticularly those of radiant character in which a maximum efficiency ofcombustion of gases or gaseous fuel is obtained.

It is well known that the contact of gaseous fuel mixtures with aradiant body and the inti-l mate mixing of gaseous combustible matterwith.

the oxygen are important factors in getting Acomplete combustion.

1 The utilization of the indirect heat from the outer surface of aradiant body or structure also aids greatly in eiiiciency of obtainingmaximum heat energy from the combustion of the fuel.

My invention contemplates structures* and principles by which all theseadvantages are attained and according to my concept the known phenomenaare combined and made possible on `an extremely simple basis ofconstruction and operation.

By providing for a succession of changes in velocities and by alternateexpansion anticom-` pressions, I obtain turbulent effects whichintimately mix the oxygen of combustion with the combustion gas inextended contact with radiant surfaces which are brought to andmaintained at highly efficient temperatures. To this end I alsocontemplate the efficient use of certain materials capable of becomingradiant when heated 'as will be later discussed and am able to provide aunitary basis by which needs may be met.

The various features of my invention will be considered in connectionwith an illustrative turbulent radiant structure shown in theaccompanying drawings. This is only a simple characteristic embodimentintended to be suggestive, to those skilled in the art, of the greatvariety of modications that can be and will be made for differentinstallations. In the drawings:-

Fig. 1 is a longitudinal section through a portion of a turbulentradiant combustion chamber in accordance with my invention.

5 33 Fig. 2 is a transverse section on the line 2 2,

of Fig. 1.

Fig. 3 shows a modified manner of constructing and laying the units.

Fig. 4 is a view of one form of unit in ac- 50 Icordance with myinvention suitable to be used as in Figs. l, 2 and 6 and 7.

Fig. 5 is a view comparable to a central part of Fig. 1, but showing amodification. Fig. 6 is a plan view of units of the type shown 55 inFig. 4 according to Figs. 1 and 2, and

varied structural Fig. 7 is a similar view of an assembly of units ofmodified form.

`In the embodiment shown, the combustible mixture is admitted into theinlet flue A at the left of Fig. 1 and passes upward through a series 60of sub-combustion or plenum chambers B fed by communicating inlets C andD. In these the effective opening of C has a cross section twice that ofthe opening D so that these combined areasfgive an'unbalanced crosssection of varied 65' turbulent effect on the gas flow into B.

As shown in Fig. 3, the inlet passages D may provide graduated centralconstrictions between thel sub-chambersor Vplenum capacities which theyconnect. The gases are compressed in their transitof D' and theirvelocity increased. The discharge4 of C whileexerting contraction andcompression prior to expansion, is more turbulent." i

The gaseous products of combustion pass to an outlet iiue E, if`desirable, or such may be omitted and the top of the combustion zoneleft open:

The disposition of the inlet and outlet connection or flues, which maybe straight or V tapered, may be horizontal or vertical, and the trendor drift of the gases varied accordingly.

As will be explained later, this is a simple matter in accordance withmy concept by a laying of the units in proper relation or in relativelyT proportioning the same.

j As shown in Fig. 1, the number l, number 2 and number 3 courses give azigzag effect. The drift starts at the number 2 course to trend leftshifting at courses 6 to 9 to drift to the right. 903

In Fig. 5 I have illustrated what may be termed, an alternate zigzagwhich provides for further Variations in the arrangement of thesub-chambers and connecting passages.

The units may be conveniently molded in the Y hollow form shown in Fig.4 and laid end to end in courses as in Fig. 6. In this form, the chamberB is enclosed by side walls 1 connected by cross webs or end walls 2leaving projecting iianges 3 which are staggered at opposite ends 100 tointerlock, leaving the restricted passages D between the ends ofadjacent units.

In the form shown in the plan View Fig. '7 the units are formed ingeneral H shape. The side walls 11 are connected by a pair of central105 cross webs 12 the ends of the side walls being alternately flangedas at 13 to interlock and make a tight joint across the sub-chambers B1.

Refractory materials of relatively high thermal conductivity lendthemselves to the making 1m1- of such a combustion chamber asconstitutes my invention as the outer surface will more quickly arriveat a temperature which gives oif radiant heat. Assuming that a re clayrefractory has a thermal conductivity of 1, other refractory materialscan be listed in the yorder of their relative conductivity, silicae,alumina 7, silicon carbide 9. Bondd silicon carbide may be used as therefractory, and-it would be obvious to one skilled in the art to usesuch a material where quick radiant temperature of the outer surface ofthe chamberk is desired."l i

However, refractory materials having high. thermal conductivity have lowthermal capacity.

Fire clay refractories have high thermal capa,-

city. A greater amount of heat is'n'eeded -toY bring the body to radiantheat, but such a body cools more slowly. When a -re clay body'hasreached the state of giving olf radiantv heat at more energy Aisrequired to maintain the radiant temperature than is required tomaintain a like condition in a body composed vof a refractory having ahigh thermal conductivity. 'Ihis has 2521 led to the preferred use in`my invention of a refractory composed cfsilicon carbide, alumina andfire clay,- 'Ijhisfrefractorybodywill more quickly reach a desired hightemperature than a re clay body, but not as vquickly as a body 3503composed lprincipally-of silicon carbide; but it will give ;offfrom the,outer surface as much heat as, yand be more effectivein promotingcombustion'A than .the innersurface, -with which the `combustion gasesare in contact; will be at.

35119,l slightly higher temperature than would be, under likeconditionsY, of heat reception, a body composed principally of silicon carbide;and the heat 'required to maintain the] temperature equilibrium will' belittle or no more thanthat 4g; required when the body is composedprincipally of silicon lcarbide; and last,4 .the outer surface willretain a radiant temperature longer, that is, will not cool as quicklyyas if the body werel composed principally of silicon carbide. ObjLviously a bonded, alumina Yrefractory may be used as a substitute forthepreferred refractory.

As an example of my preferred refractory body for my units, I use amixture of 50% silicon carbide, 40'% fused alumina, rand 10% clay; or Imay vuse a mixture composed of 50% vsilicon carbide, 39% fused aluminaIand 411%l b'o'ndy Either one of.V these bodiesv whenformed. into thedesired lrefractory shape Lwillfshow a fairly high'v thermalconductivity and a higher thermal capacity than abody containing say 92%silicon carbide and 8% clayV-such a body beingcomposed principally4 ofsilicon carbide. j

Bonded silicon carbide has a thermal conlhas a lower thermalconductivity than bonded "silicon carbide, but a higher thermalcapacity. "Either )preferred body is developed to be substantiallyimpervious to gases.

the desired rate from the outer surface, 'little' vidingspaced-restricted passages of centrally ductivity of'.o231lgram caloriesat wordend' a specific heat of approximately 0.185. The preferred bodygiven above has a thermal conductivity of approximately .015 and aspecific heat vof about 0.230. Bonded alumina has a thermal conductivityof .0083 gram calories and a specic heat of .279. VA fire clay vbody hasa thermal conductivity'of 1,.0039 `and a specific heat of 0.265.

' It can be readily seen that the preferred body The second body isunusually satisfactory -in regard to gas permeation. 'It can bereadily'seen that impermeability of thebody is,l of paramount importancein the successful use of this radiant body.

While these refractory bodies are indicated as .,preferred, lbondedalumina or other refractory mixes may'be used in making my units. 95

What I .therefore `clainrrand 4de sireto secure and outlet draft...connections v. and comprising superimposedfcourses ofLv hollowkrefractory units, consisting of :radiant sidewalls and `connectingtransverse Vwebs laid up intermediately lto dene in ,thesuccessivecourses series of relatively staggered Vcombustionvsubs-chambers, the iweb portions` of the courses partially, blockingthe top and bottom g, sides of the adjacent chambers but prof reducedkcrossl sections; .communicating between successive. chamberswhich-passages discharge into'thezsub-chambers to .effect turbulentexpansion therein. u A, f-

BJ'A combustion chamber unit adapted -to be laidup in sassembly in 'aradiant structure, comprising Ya hollow refractory article vconsistingof side and 4end .wa-llsand including an interior expansion chamber..'and a` by-passl adapted to. effect a connection between adjacentexpansion chambers when assembled in staggeredrelation with like .unitsthereabove and therebelow.

sAMUELF. WAL'roN.

